【作者】 苗恩铭；

【导师】 费业泰；

【作者基本信息】 合肥工业大学 ， 精密仪器及机械， 2004， 博士

【摘要】 现代科技迅速发展，使得精密工程的精度等级不断提高，已进入微纳米级水平。由于热变形对精度影响的重要性，所以对热变形影响机理和控制研究越来越受到国内外学者的关注。本文在国家自然科学基金“机械配合热变形误差的基础理论与应用技术研究”(项目编号：50075023)的支持下，同时参考台湾科学技术委员会的相关项目内容，在国内外热变形研究理论成果的基础上，对零件形体因素所引起的热变形及相关内容进行了系统深入的理论研究，建立了零件典型形体因素对热变形影响的数学模型，并通过实验给以论证。在此成果基础上，对材料精确热膨胀系数作了大量的理论和实验研究，为未来建立标准的精密工程中常用材料精确热膨胀系数提供了一定的参考依据。 本文主要工作和创新性成果包括： 本课题在吸收国内外热变形理论研究成果的基础上，通过热变形与力学模型的转换，对典型零件形体热变形规律进行深入的理论研究，对常见的方体、圆柱体、园环和球体等形体特征参数对零件的热变形影响给出了理论分析，首次推导建立了零件热变形规律的数学模型。 在典型零件形体热变形数学建模分析中，应用差分算法并进行了改进，将差分法发展成可得出形体热变形一般规律的解析法，有效的解决了热变形形体建模问题，为进一步研究复杂形体对零件热变形影响规律提供了一种算法。 对材料的精确热膨胀系数进行了全面与深化研究，分析了传统材料热膨胀系数的不足，给出了传统材料膨胀系数实用的精确定量评述和适用范围，提出了精确材料热膨胀系数相关问题的解决方法。同时对现行的几种材料热膨胀系数定义进行了系统分析，给出各种定义的材料热膨胀系数的精度范围，提供了在实践应用中选用原则和方法，该内容具有重要的实用价值。进一步对以圆柱体和球体为标准样件所定义的材料膨胀系数进行了理论分析，提出以圆球体为标准试件所测出的材料膨胀系数具有更好的科学性，为建立科学的精确热膨胀系数提供理论依据。 根据对热膨胀系数的理论研究成果，进一步研究了常用材料的精确膨胀系数，对本校选用的精密机械工程中常用的25种材料和台湾成功大学提供的16种(每种有4件尺寸不同的样件，共64件)材料的热膨胀系数变化规律进行了测定，给出了实用数表，并对其实验数据进行了分析比较，得出了材料精确热膨胀系数的主要结论，为今后进一步研究海峡两岸统一的材料精确热膨胀系数标准提供了良好依据。合肥工业大学博士学位论文 研制成功了国内唯一的高精度三维热变形实验装置一均匀温度场高精度实验装置，该装置具有恒温箱微机控制，高精度电感测头准确定位，微动三维工作台和双频激光干涉仪热变形量测量系统，极大的提高了测量精度和测量适用范围，扩展了其应用功能。其主要技术指标是:容积为820 x 528 x 85Omm3，测温不确定度为0.02℃，微变形测量不确定度为士0.28声刀”。该实验装置的研制成功为进一步在本方向的研究给以了设备保障。关键词:热变形、热膨胀系数、热应力、热传导、差分法更多还原

【Abstract】 With mechanical precision improving from micron scale to nanometer scale in modern times, scientists in world more and more pay attention to the influence of thermal deformation in precise process and precision instruments. Under thesustentation of NSFC(National Nature Science Foundation of China) project "theoretical and applied research of mechanical assort thermal deformation errors" (item number: 50075023) and Taiwan Science and Technology Committee project, This paper summarizes domestic and abroad thermal deformation achievements; .systematically studied mechanical parts’ thermal deformation influenced by mechanical parts body factor; establishes thermal deformation mathematics model with mechanical parts body factors, and the model is demonstrated by experiments. On the basis of these achievements, the material precise coefficients of thermal expansion are deduced and a large number of experiments are made to prove these results. On the base of these theoretical and experimental achievements, the standard material precise coefficient of thermal expansion in precision engineering can advance further.The main contents and innovations of the dissertation include: On the basis of synthetically analysis about domestic and abroad achievements, by transforming thermal deformation and mechanics model, the rule of typical parts body’s thermal deformation is researched, theoretical analysis on rules of square body, cylinder and sphere thermal deformation are given, and parts thermal deformation mathematics model is deduced for the first time.In the analysis of typical parts body thermal deformation mathematics model, the typical finite difference method is developed into an analysis method which can be used to acquired the general rule of the body thermal deformation, and this analysis method provides a kind of effectual arithmetic in researching parts thermal deformation with complex shape parts.This paper comprehensively studies material precise coefficient of thermal expansion, analyzes the defect of the traditional material coefficient of thermal expansion, demonstrates the quantitative evaluation and applicable scale of the precision under traditional material coefficient of thermal expansion, gives the solution to obtain material precise coefficient of thermal expansion. Meanwhile,this paper analyzes several current definitions of material coefficient of thermal expansion, demonstrates the precision range with different coefficient definitions, gives the principle and method in the application and industry, and this theory possesses important practical value. We theoretically analyzes material coefficient of thermal expansion defined by the cylinder and sphere standard samples, the material coefficient by measuring sphere standard is more scientific. This paper establishes mathematics model of coefficient of thermal expansion with typical shape parts to provide theoretically basis for establishing more scientific precise coefficient of thermal expansion.This paper studies the changing rule of material coefficient of thermal expansion with different sample parts, including 25 kinds of general material in precision engineering and 16 kinds of material (one kind of material includes 4 different dimension samples, altogether 64 pieces) provided by Taiwan National Chengkung University, their coefficient was tested through experiments, as the information of the material precise coefficient of thermal deformation, these data were analyzed and the important theoretical achievements have acquired, those results will help establish the uniform standard material precise coefficient of thermal deformation.This paper develops high-precision three dimension thermal deformation experiment instrument ?even temperature field high-precision experiment instrument, it has constant temperature cabinet controlled by microcomputer, located by inductance measuring probes, three dimension jiggle desk and double-frequency laser interferometer measuring system, these function developed to enhance its applicability. The high-precision three更多还原